linux/arch
Tushar Behera d6838a62b4 ARM: SAMSUNG: Use spin_lock_{irqsave,irqrestore} in clk_set_rate
The spinlock clocks_lock can be held during ISR, hence it is not safe to
hold that lock with disabling interrupts.

It fixes following potential deadlock.

=========================================================
[ INFO: possible irq lock inversion dependency detected ]
3.6.0-rc4+ #2 Not tainted
---------------------------------------------------------
swapper/0/1 just changed the state of lock:
 (&(&host->lock)->rlock){-.....}, at: [<c027fb0d>] sdhci_irq+0x15/0x564
but this lock took another, HARDIRQ-unsafe lock in the past:
 (clocks_lock){+.+...}

and interrupts could create inverse lock ordering between them.

other info that might help us debug this:
 Possible interrupt unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(clocks_lock);
                               local_irq_disable();
                               lock(&(&host->lock)->rlock);
                               lock(clocks_lock);
  <Interrupt>
    lock(&(&host->lock)->rlock);

 *** DEADLOCK ***

Signed-off-by: Tushar Behera <tushar.behera@linaro.org>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
2012-09-18 10:05:34 +09:00
..
alpha alpha: Fix fall-out from disintegrating asm/system.h 2012-08-19 08:41:19 -07:00
arm ARM: SAMSUNG: Use spin_lock_{irqsave,irqrestore} in clk_set_rate 2012-09-18 10:05:34 +09:00
avr32 ipc: use Kconfig options for __ARCH_WANT_[COMPAT_]IPC_PARSE_VERSION 2012-07-30 17:25:21 -07:00
blackfin Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k 2012-08-03 10:52:41 -07:00
c6x Enable atomic64 ops in C6X 2012-08-17 08:10:12 -07:00
cris ipc: use Kconfig options for __ARCH_WANT_[COMPAT_]IPC_PARSE_VERSION 2012-07-30 17:25:21 -07:00
frv Merge branch 'akpm' (Andrew's patch-bomb) 2012-07-30 17:25:34 -07:00
h8300 ipc: use Kconfig options for __ARCH_WANT_[COMPAT_]IPC_PARSE_VERSION 2012-07-30 17:25:21 -07:00
hexagon Merge branch 'trivial' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild 2012-07-30 11:24:53 -07:00
ia64 [IA64] defconfig: Remove CONFIG_MISC_DEVICES 2012-08-20 13:04:29 -07:00
m32r ipc: use Kconfig options for __ARCH_WANT_[COMPAT_]IPC_PARSE_VERSION 2012-07-30 17:25:21 -07:00
m68k m68k: select CONFIG_GENERIC_ATOMIC64 for all m68k CPU types 2012-08-17 10:04:24 +10:00
microblaze Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k 2012-08-03 10:52:41 -07:00
mips MIPS: pci-ar724x: avoid data bus error due to a missing PCIe module 2012-08-23 15:44:47 +02:00
mn10300 Merge branch 'akpm' (Andrew's patch-bomb) 2012-07-30 17:25:34 -07:00
openrisc
parisc [PARISC] fix personality flag check in copy_thread() 2012-08-03 11:25:12 +01:00
powerpc Merge branch 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc 2012-08-25 17:30:18 -07:00
s390 s390/32: Don't clobber personality flags on exec 2012-08-30 16:28:07 +02:00
score
sh Merge branches 'sh/urgent' and 'sh/gpiolib' into sh-latest 2012-08-09 13:21:13 +09:00
sparc sparc64: Be less verbose during vmemmap population. 2012-08-15 00:37:29 -07:00
tile memcg: rename config variables 2012-07-31 18:42:43 -07:00
um Merge branch 'for-linus-3.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml 2012-08-01 16:45:02 -07:00
unicore32 PCI changes for the 3.6 merge window: 2012-07-24 16:17:07 -07:00
x86 KVM: x86: fix KVM_GET_MSR for PV EOI 2012-08-27 18:03:05 -03:00
xtensa xtensa: select generic atomic64_t support 2012-07-31 18:42:39 -07:00
.gitignore
Kconfig ipc: use Kconfig options for __ARCH_WANT_[COMPAT_]IPC_PARSE_VERSION 2012-07-30 17:25:21 -07:00